US3387865A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drill string concept
Assignee: Northrop Grumman Corp
•
Filing: 1966-08-29
•
Granted: 1968-06-11
•
Expires: 1986-08-29
Abstract
No abstract record available.
Inventors
- 👤 Donald E Ross
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:23
CPC Classifications
F; F16; F16L; F16L37/00; F16L37/08; F16L37/12; F16L37/1215; E; E21; E21B; E21B17/00; E21B17/02; E21B17/04; E21B17/046; Y; Y10; Y10T; Y10T279/00; Y10T279/10; Y10T279/1004; Y10T279/1008; Y10T279/1037; Y10T279/1041; Y10T279/17; Y10T279/17666; Y10T279/17692; Y10T279/17717; Y10T403/00; Y10T403/55; Y10T403/70; Y10T403/7045
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US770519A
Cited
US2152429A
Cited
US2444414A
Cited
US2508039A
Cited
US3074746A
Cited
US3255822A
Cited
DE1179889B
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-06-11 | 1971-12-11 | 1972-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-06-11 | 1975-12-11 | 1976-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-06-11 | 1979-12-11 | 1980-06-11 | $7700.00 | Window Closed / Lapsed |